1 /*****************************************************************************
2 * mpeg4audio.c: parse and packetize an MPEG 4 audio stream
3 *****************************************************************************
4 * Copyright (C) 2001, 2002 VideoLAN
5 * $Id: mpeg4audio.c,v 1.10 2003/10/23 20:51:20 gbazin Exp $
7 * Authors: Laurent Aimar <fenrir@via.ecp.fr>
8 * Gildas Bazin <gbazin@netcourrier.com>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
23 *****************************************************************************/
25 /*****************************************************************************
27 *****************************************************************************/
28 #include <stdlib.h> /* malloc(), free() */
29 #include <string.h> /* strdup() */
33 #include <vlc/decoder.h>
34 #include <vlc/input.h>
38 #include "vlc_block_helper.h"
42 * AudioObjectType 5 bits
43 * samplingFrequencyIndex 4 bits
44 * if (samplingFrequencyIndex == 0xF)
45 * samplingFrequency 24 bits
46 * channelConfiguration 4 bits
48 * FrameLengthFlag 1 bit 1024 or 960
49 * DependsOnCoreCoder 1 bit (always 0)
50 * ExtensionFlag 1 bit (always 0)
53 /*****************************************************************************
54 * decoder_sys_t : decoder descriptor
55 *****************************************************************************/
64 block_bytestream_t bytestream;
67 * Packetizer output properties
69 sout_packetizer_input_t *p_sout_input;
70 sout_format_t sout_format;
71 sout_buffer_t * p_sout_buffer; /* current sout buffer */
76 audio_date_t end_date;
79 int i_frame_size, i_raw_blocks;
80 unsigned int i_channels;
81 unsigned int i_rate, i_frame_length;
93 static int i_sample_rates[] =
95 96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050,
96 16000, 12000, 11025, 8000, 7350, 0, 0, 0
99 #define ADTS_HEADER_SIZE 6
101 /****************************************************************************
103 ****************************************************************************/
104 static int OpenPacketizer( vlc_object_t * );
105 static int InitPacketizer( decoder_t * );
106 static int RunFramePacketizer ( decoder_t *, block_t * );
107 static int RunADTSPacketizer ( decoder_t *, block_t * );
108 static int EndPacketizer ( decoder_t * );
109 static int GetSoutBuffer( decoder_t *, sout_buffer_t ** );
111 static int ADTSSyncInfo( decoder_t *, const byte_t * p_buf,
112 unsigned int * pi_channels,
113 unsigned int * pi_sample_rate,
114 unsigned int * pi_frame_length,
115 unsigned int * pi_raw_blocks );
117 /*****************************************************************************
119 *****************************************************************************/
121 set_description( _("MPEG4 Audio packetizer") );
122 set_capability( "packetizer", 50 );
123 set_callbacks( OpenPacketizer, NULL );
126 /*****************************************************************************
127 * OpenPacketizer: probe the packetizer and return score
128 *****************************************************************************/
129 static int OpenPacketizer( vlc_object_t *p_this )
131 decoder_t *p_dec = (decoder_t*)p_this;
133 if( p_dec->p_fifo->i_fourcc != VLC_FOURCC( 'm', 'p', '4', 'a' ) )
138 /* Allocate the memory needed to store the decoder's structure */
140 (decoder_sys_t *)malloc(sizeof(decoder_sys_t)) ) == NULL )
142 msg_Err( p_dec, "out of memory" );
146 p_dec->pf_init = InitPacketizer;
147 p_dec->pf_decode = RunFramePacketizer;
148 p_dec->pf_end = EndPacketizer;
153 /*****************************************************************************
154 * InitPacketizer: Initalize the packetizer
155 *****************************************************************************/
156 static int InitPacketizer( decoder_t *p_dec )
158 decoder_sys_t *p_sys = p_dec->p_sys;
161 p_sys->i_state = STATE_NOSYNC;
163 aout_DateSet( &p_sys->end_date, 0 );
165 p_sys->p_sout_input = NULL;
166 p_sys->p_sout_buffer = NULL;
167 p_sys->p_chain = NULL;
169 msg_Info( p_dec, "Running MPEG4 audio packetizer" );
171 p_wf = (WAVEFORMATEX*)p_dec->p_fifo->p_waveformatex;
173 if( p_wf && p_wf->cbSize > 0)
175 uint8_t *p_config = (uint8_t*)&p_wf[1];
178 i_index = ( ( p_config[0] << 1 ) | ( p_config[1] >> 7 ) ) & 0x0f;
179 if( i_index != 0x0f )
181 p_sys->i_rate = i_sample_rates[i_index];
182 p_sys->i_frame_length = (( p_config[1] >> 2 ) & 0x01) ? 960 : 1024;
186 p_sys->i_rate = ( ( p_config[1] & 0x7f ) << 17 ) |
187 ( p_config[2] << 9 ) | ( p_config[3] << 1 ) |
188 ( p_config[4] >> 7 );
189 p_sys->i_frame_length = (( p_config[4] >> 2 ) & 0x01) ? 960 : 1024;
192 msg_Dbg( p_dec, "AAC %dHz %d samples/frame",
193 p_sys->i_rate, p_sys->i_frame_length );
195 p_sys->i_channels = p_wf->nChannels;
196 p_sys->sout_format.i_extra_data = p_wf->cbSize;
197 p_sys->sout_format.p_extra_data = malloc( p_wf->cbSize );
198 memcpy( p_sys->sout_format.p_extra_data, &p_wf[1], p_wf->cbSize );
202 msg_Dbg( p_dec, "No decoder specific info, must be an ADTS stream" );
204 /* We will try to create a AAC Config from adts */
205 p_sys->sout_format.i_extra_data = 0;
206 p_sys->sout_format.p_extra_data = NULL;
207 p_dec->pf_decode = RunADTSPacketizer;
213 /****************************************************************************
214 * RunFramePacketizer: the whole thing
215 ****************************************************************************
216 * This function must be fed with complete frames.
217 ****************************************************************************/
218 static int RunFramePacketizer( decoder_t *p_dec, block_t *p_block )
220 decoder_sys_t *p_sys = p_dec->p_sys;
222 if( !aout_DateGet( &p_sys->end_date ) && !p_block->i_pts )
224 /* We've just started the stream, wait for the first PTS. */
225 block_Release( p_block );
229 p_sys->pts = p_block->i_pts;
230 p_sys->i_frame_size = p_block->i_buffer;
232 if( GetSoutBuffer( p_dec, &p_sys->p_sout_buffer ) != VLC_SUCCESS )
237 /* Copy the whole frame into the buffer */
238 p_dec->p_vlc->pf_memcpy( p_sys->p_sout_buffer->p_buffer,
239 p_block->p_buffer, p_block->i_buffer );
241 sout_InputSendBuffer( p_sys->p_sout_input, p_sys->p_sout_buffer );
242 p_sys->p_sout_buffer = NULL;
244 block_Release( p_block );
248 /****************************************************************************
249 * RunADTSPacketizer: the whole thing
250 ****************************************************************************/
251 static int RunADTSPacketizer( decoder_t *p_dec, block_t *p_block )
253 decoder_sys_t *p_sys = p_dec->p_sys;
254 uint8_t p_header[ADTS_HEADER_SIZE];
256 if( !aout_DateGet( &p_sys->end_date ) && !p_block->i_pts )
258 /* We've just started the stream, wait for the first PTS. */
259 block_Release( p_block );
263 if( p_block->b_discontinuity )
265 p_sys->i_state = STATE_SYNC;
270 block_ChainAppend( &p_sys->p_chain, p_block );
274 block_ChainAppend( &p_sys->p_chain, p_block );
275 p_sys->bytestream = block_BytestreamInit( p_dec, p_sys->p_chain, 0 );
280 switch( p_sys->i_state )
284 while( block_PeekBytes( &p_sys->bytestream, p_header, 2 )
287 /* Look for sync word - should be 0xfff + 2 layer bits */
288 if( p_header[0] == 0xff && (p_header[1] & 0xf6) == 0xf0 )
290 p_sys->i_state = STATE_SYNC;
293 block_SkipByte( &p_sys->bytestream );
295 if( p_sys->i_state != STATE_SYNC )
297 if( block_PeekByte( &p_sys->bytestream, p_header )
298 == VLC_SUCCESS && p_header[0] == 0xff )
300 /* Start of a sync word, need more data */
304 block_ChainRelease( p_sys->p_chain );
305 p_sys->p_chain = NULL;
312 /* New frame, set the Presentation Time Stamp */
313 p_sys->pts = p_sys->bytestream.p_block->i_pts;
314 if( p_sys->pts != 0 &&
315 p_sys->pts != aout_DateGet( &p_sys->end_date ) )
317 aout_DateSet( &p_sys->end_date, p_sys->pts );
319 p_sys->i_state = STATE_HEADER;
323 /* Get ADTS frame header (ADTS_HEADER_SIZE bytes) */
324 if( block_PeekBytes( &p_sys->bytestream, p_header,
325 ADTS_HEADER_SIZE ) != VLC_SUCCESS )
331 /* Check if frame is valid and get frame info */
332 p_sys->i_frame_size = ADTSSyncInfo( p_dec, p_header,
335 &p_sys->i_frame_length,
336 &p_sys->i_raw_blocks );
337 if( !p_sys->i_frame_size )
339 msg_Dbg( p_dec, "emulated sync word" );
340 block_SkipByte( &p_sys->bytestream );
341 p_sys->i_state = STATE_NOSYNC;
345 p_sys->i_state = STATE_DATA;
348 /* TODO: If p_block == NULL, flush the buffer without checking the
351 /* Check if next expected frame contains the sync word */
352 if( block_PeekOffsetBytes( &p_sys->bytestream,
353 p_sys->i_frame_size, p_header, 2 )
360 if( p_header[0] != 0xff || (p_header[1] & 0xf6) != 0xf0 )
362 msg_Dbg( p_dec, "emulated sync word "
363 "(no sync on following frame)" );
364 p_sys->i_state = STATE_NOSYNC;
365 block_SkipByte( &p_sys->bytestream );
369 if( !p_sys->p_sout_buffer )
370 if( GetSoutBuffer( p_dec, &p_sys->p_sout_buffer ) != VLC_SUCCESS )
375 /* Copy the whole frame into the buffer */
376 if( block_GetBytes( &p_sys->bytestream,
377 p_sys->p_sout_buffer->p_buffer,
378 p_sys->i_frame_size ) != VLC_SUCCESS )
384 p_sys->p_chain = block_BytestreamFlush( &p_sys->bytestream );
386 sout_InputSendBuffer( p_sys->p_sout_input, p_sys->p_sout_buffer );
388 p_sys->i_state = STATE_NOSYNC;
389 p_sys->p_sout_buffer = NULL;
391 /* Make sure we don't reuse the same pts twice */
392 if( p_sys->pts == p_sys->bytestream.p_block->i_pts )
393 p_sys->pts = p_sys->bytestream.p_block->i_pts = 0;
400 /*****************************************************************************
402 *****************************************************************************/
403 static int GetSoutBuffer( decoder_t *p_dec, sout_buffer_t **pp_buffer )
405 decoder_sys_t *p_sys = p_dec->p_sys;
407 if( p_sys->p_sout_input != NULL &&
408 ( p_sys->sout_format.i_sample_rate != (int)p_sys->i_rate
409 || p_sys->sout_format.i_channels != (int)p_sys->i_channels ) )
411 /* Parameters changed - this should not happen. */
414 /* Creating the sout input if not created yet. */
415 if( p_sys->p_sout_input == NULL )
417 p_sys->sout_format.i_cat = AUDIO_ES;
418 p_sys->sout_format.i_fourcc = VLC_FOURCC( 'm', 'p', '4', 'a' );
419 p_sys->sout_format.i_sample_rate = p_sys->i_rate;
420 p_sys->sout_format.i_channels = p_sys->i_channels;
421 p_sys->sout_format.i_block_align = 0;
422 p_sys->sout_format.i_bitrate = 0;
424 aout_DateInit( &p_sys->end_date, p_sys->i_rate );
425 aout_DateSet( &p_sys->end_date, p_sys->pts );
427 p_sys->p_sout_input = sout_InputNew( p_dec, &p_sys->sout_format );
428 if( p_sys->p_sout_input == NULL )
430 msg_Err( p_dec, "cannot add a new stream" );
434 msg_Info( p_dec, "AAC channels: %d samplerate: %d",
435 p_sys->i_channels, p_sys->i_rate );
438 *pp_buffer = sout_BufferNew( p_sys->p_sout_input->p_sout,
439 p_sys->i_frame_size );
440 if( *pp_buffer == NULL )
445 (*pp_buffer)->i_pts =
446 (*pp_buffer)->i_dts = aout_DateGet( &p_sys->end_date );
448 (*pp_buffer)->i_length =
449 aout_DateIncrement( &p_sys->end_date, p_sys->i_frame_length )
450 - (*pp_buffer)->i_pts;
455 /*****************************************************************************
456 * EndPacketizer: clean up the packetizer
457 *****************************************************************************/
458 static int EndPacketizer( decoder_t *p_dec )
460 if( p_dec->p_sys->p_sout_input != NULL )
462 if( p_dec->p_sys->p_sout_buffer )
464 sout_BufferDelete( p_dec->p_sys->p_sout_input->p_sout,
465 p_dec->p_sys->p_sout_buffer );
468 sout_InputDelete( p_dec->p_sys->p_sout_input );
471 if( p_dec->p_sys->p_chain ) block_ChainRelease( p_dec->p_sys->p_chain );
473 free( p_dec->p_sys );
478 /*****************************************************************************
479 * ADTSSyncInfo: parse MPEG 4 audio ADTS sync info
480 *****************************************************************************/
481 static int ADTSSyncInfo( decoder_t * p_dec, const byte_t * p_buf,
482 unsigned int * pi_channels,
483 unsigned int * pi_sample_rate,
484 unsigned int * pi_frame_length,
485 unsigned int * pi_raw_blocks_in_frame )
487 decoder_sys_t *p_sys = p_dec->p_sys;
488 int i_id, i_profile, i_sample_rate_idx, i_frame_size;
490 /* Fixed header between frames */
491 i_id = ( (p_buf[1] >> 3) & 0x01 ) ? 2 : 4;
492 i_profile = p_buf[2] >> 6;
493 i_sample_rate_idx = (p_buf[2] >> 2) & 0x0f;
494 *pi_sample_rate = i_sample_rates[i_sample_rate_idx];
495 *pi_channels = ((p_buf[2] & 0x01) << 2) | ((p_buf[3] >> 6) & 0x03);
497 /* Variable header */
498 i_frame_size = ((p_buf[3] & 0x03) << 11) | (p_buf[4] << 3) |
499 ((p_buf[5] >> 5) & 0x7);
500 *pi_raw_blocks_in_frame = (p_buf[6] & 0x02) + 1;
502 if( !*pi_sample_rate || !*pi_channels || !i_frame_size )
508 *pi_frame_length = 1024;
510 /* Build the decoder specific info header */
511 if( !p_dec->p_sys->sout_format.i_extra_data )
513 p_sys->sout_format.i_extra_data = 2;
514 p_sys->sout_format.p_extra_data = malloc( 2 );
515 p_sys->sout_format.p_extra_data[0] =
516 (i_profile + 1) << 3 | (i_sample_rate_idx > 1);
517 p_sys->sout_format.p_extra_data[1] =
518 ((i_sample_rate_idx & 0x01) << 7) | (*pi_channels <<3);